Tag Archives: Coma

Leukoencephalopathy (white matter disease)

Damage to white matter may occur due to may conditions that can affect the brain. The clinical features, prognosis and treatment are related to the underlying condition Clinical features: There is a wide range of symptoms: Rapidly progressive dementia/subacute encephalopathy, lower body parkinsonism/gait apraxia, behavioural changes, pseudobulbar speech and pseudobulbar affect may occur Later on … Continue reading Leukoencephalopathy (white matter disease)

Bickerstaff Brainstem Encephalitis (BBE)

Diagnosis: Clinical features plus antibody tests Clinical features: Decreased level of consciousness, areflexia Findings on Investigations: Anti-GQ1b IgG antibody: positive Treatment: Intravenous Immunoglobulin IVIG  

Osmotic Demyelination Syndrome

Synonyms: central pontine myelinolysis, and extrapontine myelinolysis Diagnosis: Clinical features plus MRI plus history of rapid change (increase or decrease) in sodium levels Clinical features: Encephalopathy, coma, quadriparesis, upper motor neuron signs, dysphagia Findings on Investigations: MRI : T2 : high signal in pons, basal ganglia, thalami FLAIR: high signal in pons, basal ganglia, thalami Treatment: Supportive … Continue reading Osmotic Demyelination Syndrome

Organic-Solvent Related Acute Leukoencephalopathy

Diagnosis: Clincial features, exposure to solvent and MRI Clinical features: Solvent exposure Rapidly progressive dementia, akinetic mute, other features Findings on Investigations: MRI: Diffuse symmetric involvement of white matter Pathology: PAS-positive macrophages Electron microscopy EM: membrane-bound lamellar material within macrophage Treatment: Supportive care Related articles: Approach to cognitive impairment, approach to acute confusion, Leukoencephalopathy, Acute … Continue reading Organic-Solvent Related Acute Leukoencephalopathy

Heroin related Acute leukoencephalopathy “chasing the dragon"

Diagnosis: Clinical features plus MRI Clinical features: Initially: Ataxia, dysmetria, and dysarthria, gait abnormalities Later on: akinetic mute, spastic quadraparesis, After recover: tremor Inhalation of vaporised heroin (heroin pyrolysate) “chasing the dragon” Findings on Investigations: MRI: Involvement of white matter (cerebellum, posterior cerebrum, posterior limbs of the internal capsule, splenium of the corpus callosum, medial … Continue reading Heroin related Acute leukoencephalopathy “chasing the dragon"

Diffuse Axonal Injury

Diagnosis: Neuroimaging +Clinical features Clinical features: Coma after head trauma: low GCS <8, with or without features to suggest structural cause (dilated pupills, disconjugate gaze, asymmetric posturing) Raise intracranial pressure (ICP ) often occurs Neuroimaging: CT: May be normal May show petechial hemorrhages in the whitematter (corpus callosum, corona radiata, cerebral peduncles) May show diffuse … Continue reading Diffuse Axonal Injury

Cerebral Contusion

Diagnosis: CT: Cerebral edema (hypodensity on CT) in the cortex or lobe at  the site of injury or opposite location (counter-coup) or distant site where impact occurs at areas of the skull Hemorrhage (hyperdensity on CT) within the areas of contusion are typical. They involve the cortex and extend subcortically to a variable extent Frontal … Continue reading Cerebral Contusion

Subdural Hematoma

Synonyms: Subdural haematoma Diagnosis: CT: Crescent shaped, diffuse covering a large part of the hemisphere Can be biconvex in shape Can be of mixed density: e.g. Fluid-fluid level Cross suture lines but not the midline Variation with time: Acute, hyperdense, homogenous Middle, isodense with brain Chronic: hypodense Acute on chronic: heterogenous, fluid-fluid levels Pathology: Acute: … Continue reading Subdural Hematoma

Epidural Hematoma

Synonyms: Extradural hematoma Diagnosis: CT or MRI: Biconvex shape a.k.a. ‘lentiform’, usually over the temporal lobe Can cross the falx, tentorium, can cross the midline, but doesn’t cross the suture lines Associated with skull fracture Clinical features: Usually there is a history of trauma Often the patient is knocked unconscious with the initial trauma. They … Continue reading Epidural Hematoma

Traumatic Brain Injury

Synonyms and related terms: Head trauma a.k.a. head injury a.k.a. traumatic brain injury TBI Diagnosis: Clinical With or without neuroimaging: CT more commonly than MRI, Classification, the Glasgow coma scale GCS was designed for this: Mild: GCS 13-15 Moderate: GCS 9-12 Severe: GCS = or <8 Critical: GCS 3-4 Treatment: If mild: Consider discharge or … Continue reading Traumatic Brain Injury

Anoxic Brain Injury

Synonyms: Global cerebral ischemia a.k.a. global/diffuse cerebral hypoxia ischemia a.k.a. hypoxic ischemic encephalopathy a.k.a. Postanoxic Encephalopahty Diagnosis: Clinical features with or without MRI Clinical features: Coma after pulseless cardiac arrest or after significant hypoxia Episode of brain anoxia/global ischemia. Myoclonic status epilepticus may occur (may involve face, trunk, limbs) Findings on investigations: MRI: T2/FLAIR hyperintensity … Continue reading Anoxic Brain Injury

Subarachnoid Hemorrhage

Synonyms: Subarachnoid haemorrhage Diagnosis: Findings on Investigations: Diagnosis is established by neuroimaging (CT or MRI) or by lumbar puncture Non-contrast CT: Demonstrates subarachnoid hemorrhage in the acute phase. May be negative, but is positive in the majority of cases. If CT is negative LP is indicated. Blood in CSF spaces: sulci & cisterns. May also … Continue reading Subarachnoid Hemorrhage

Intracerebral Hemorrhage

This section will discuss intracerebral hemorrhage; the commonest type of hemorrhagic stroke. Hemorrhagic stroke is a broad category of stroke and includes intracerebral hemorrhage and subarachnoid hemorrhage. Together these two conditions represent 13-20% of stroke cases with the rest being due to ischemic stroke. Intracerebral hemorrhage is more common than subarachnoid hemorrhage with the later … Continue reading Intracerebral Hemorrhage

Ischemic Stroke

Ischemic stroke is the commonest form of stroke. It represents infarction of the brain or spinal cord due to interruption of blood supply. There are many causes including embolism of material such as thrombus, cholesterol or rarely other material. Other mechanisms include thrombosis and miscellaneous causes of interruption of blood flow. The symptoms vary depending … Continue reading Ischemic Stroke

Listeria Rhombencephalitis

Synonyms: Listeria brainstem encephalitis, neurolisteriosis, Listeria meningitis if without parenchymal involvement Diagnosis: Positive CSF gram stain & culture: gram positive bacillus, Listeria monocytogenes Or Positive blood culture: growing Listeria monocytogenes Listeria meningitis if without parenchymal involvement Clinical features: Fever +headache, then brainstem signs, then coma & respiratory failure Findings on Investigations: MRI: lesion in brainstem … Continue reading Listeria Rhombencephalitis


Encephalitis is the term used to describe an inflammatory process of the substance of the brain. This distinguishes it from meningitis which is an inflammatory process of the coverings of the brain. There are patients who have inflammation of both areas and this is described as meningo-encephalitis. Patients with encephalitis and those with meningitis present … Continue reading Encephalitis

Fungal Meningitis

There are various fungi that may cause meningitis. The manifestations vary by causative organism and host immune status. Some organisms are more common in certain geographical locations. Patients may present acutely with headache and encephalopathy or may have a much more indolent course.     Cryptococcal meningitis: Synonyms: Cryptococcosis (Cryptococcus neoformans) Diagnosis: Clinical findings plus … Continue reading Fungal Meningitis

Tuberculous Meningitis

Synonyms: Mycobacterium tuberculosis meningitis, TB meningitis, tuberculoma, tuberculous meningovasculitis Diagnosis: Clinical features plus confirmatory CSF analysis or TB studies Findings in Investigations: Findings remain after 10 days treatment White cell count: moderately high, Usually <500/microL, (100-300/mm3) Mainly lymphocytes Protein: High, >0.8g/L Glucose: Low ,<2.2 mmol/l Or atypically: Neutrophilia if early, normal protein, normal glucose Eosinophilia … Continue reading Tuberculous Meningitis

Bacterial Meningitis

Diagnosis: Clinical features plus confirmation by CSF analysis Findings in Bacterial meningitis: High opening pressure >180 mmH2O, turbid/purulent appearance White cell count: high, 10-10,000/microL Mainly neutrophils (usually >100), but monocytes are suggestive of Listeria monocytogenes Protein: High, >0.45 g/L (>45 mg/dL) Glucose: low, <0.4 of serum (roughly <1/2 serum), or <2.2 mmol/L (<40 mg/dL) Borrelia … Continue reading Bacterial Meningitis


Clinical features: Patients present with headache and necks stiffness. They typically have a fever, unless they are immunosupressed, and may have a rash. The classic triad in bacterial meningitis is headache, fever and rash. It is a serious life-threatening medical emergency that often results in significant disability. However, the commonest cause of meningits overall is … Continue reading Meningitis